Ten people died after the police chopper smashed through the roof of the packed pub in Glasgow on November 29, 2013, because the engines became “starved of fuel”.

The Air Accidents Investigation Branch (AAIB) yesterday said police helicopters should be equipped with black box recorders.

They made the recommendation after their report revealed pilot David Traill pressed a button to cancel low fuel warning alarms five times before crashing into the packed bar.

The probe also found two transfer pumps that could have provided fuel to the engines were turned off, and that an emergency landing procedure was not followed.

Wreck of helicopter is removed from pub

But the AAIB admitted the reasons behind the catastrophic chain of events would remain “unknown” because of the lack of an on-board flight recorder.

The Crown Office has confirmed a fatal accident inquiry will be held as soon as possible after the AAIB was published yesterday.

AAIB Chief Inspector Keith Conradi said: “We have made a series of safety recommendations in this final report including that European and British civil aviation regulators require all police and medical helicopters to carry flight recording equipment.

“We do not apportion blame in our reports.”

Aviation expert Jim Morris said he did not believe a pilot of Traill’s experience would try to reach the helicopter’s base while low on fuel.

He added: “He should have been able to competently deal with fuel management, low fuel and emergency procedures.

The report recommends that the Civil Aviation Authority requires all police helicopters to be equipped with a “black box” recorder.

It also recommends that the European Aviation Safety Agency make flight recorders mandatory for all helicopter emergency medical service operations.

The report revealed fuel pumps were switched off when the helicopter was between Dalkeith in Midlothian and Bothwell in Lanarkshire.

The Clutha Vaults bar Glasgow helicopter crash November 2013

It states that the first low fuel indicator activated somewhere before Bothwell.

Guidelines say he should have landed within 10 minutes, but did not.

The report said: “The investigation could not establish why a pilot with over 5500 hours flying experience in military and civil helicopters did not complete the actions detailed in the pilot’s checklist emergency and malfunction procedures for the low fuel warnings.”

There was also around 32 seconds between the first engine flaming out and the second – but the single engine emergency shutdown checklist was not completed in that time.

The report found no evidence of any technical malfunction, and there was fuel left in the tanks.

A Crown Office spokesman said: “The report raises a number of questions for which the families of the victims deserve answers.

Jim Morris talks to the press after relatives of crash victims met with representatives of the Air Accidents Investigation Branch (Image: Danny Lawson/PA Wire)

A FORMER RAF pilot and aviation expert has insisted pilot David Traill would not have gambled and tried to reach base while low on fuel.

Jim Morris, who works for law firm Irwin Mitchell, who represent victims of the crash, said: “I have studied a number of crashes in detail and this is up there as one of the most bizarre and inexplicable.

“There are effectively two fuel pumps to transfer fuel from the main tank to the engines’ supply tanks.

“One of these should be on at all times but at the time of the crash both were switched off, meaning the supply tanks’ fuel became exhausted and caused the double flame out, despite there being 76kg of fuel in the main tank.

“This was a highly qualified and extremely experienced former RAF helicopter pilot who was assessed as above average.

“I do not believe he would have just decided to ignore warnings and try to get back to base.

“He should have been able to competently deal with fuel management, low fuel and emergency procedures.

“The report suggests he had acknowledged low fuel warnings, but the AAIB could not establish why he did not complete the low fuel actions in the pilot’s checklist.Something simply doesn’t add up.”

Morris added: “We may never know why both pump switches were off because of a lack of flight data recorder and cockpit voice recorder.

“The crucial real time evidence from a flight recorder would have enabled the investigators to reconstruct in far more detail what the pilot and helicopter were actually experiencing and the reasons for the events.”

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